Material spotlight: ZA-27

Zinc-aluminium alloys were first introduced for gravity casting but are now sought-after materials for high-pressure, cold-chamber die casting. With zinc as the base metal, ZA-27 consists of 27 percent aluminium and 2.2 percent copper. ZA alloys have higher concentrations of aluminium than traditional zinc alloys and have unrivalled bearing properties—ZA-27 having the highest aluminium content of all three ZA alloys. Silver in colour, this zinc-aluminium combination is lightweight, dense and best suited to applications requiring optimum strength.

Benefits of ZA-27

ZA-27 provides a variety of benefits and solutions for different die casting projects. In addition to its wear resistance and high-strength properties, other specific benefits of ZA-27 include:

• High tensile & yield strength
• Corrosion resistance
• Non-sparking properties
• Hardness
• Good bearing and creep properties
• Lightweight
• Easy machinability
• Thermal conductivity
• Longer tool life
• Environmentally friendly and efficiently recyclable

ZA-27 applications

ZA-27 is an underappreciated metal for foundry applications. It is three times stronger than typical cast aluminium and can have the tensile strength of grey cast iron. At Dynacast, we have had great success casting ZA-27. One of our customers—in the safety restraint industry—needed more strength than standard aluminium alloys could offer. Our team of engineers designed the part using ZA-27 and achieved the maximum strength required without failure.

ZA-27 can be used for a variety of projects but is best suited to bearing applications. It is easily machined, and castings can be readily polished, plated, painted or anodised. Due to its high melting point, ZA-27 is suitable for projects with service temperatures of ~150 degrees Celsius. ZA-27's non-sparking characteristics enable it to function as a natural bearing, which inevitably provides cost savings as well as maintenance and reliability advantages over other cast metals—making it ideal for the automotive industry. Other industries using ZA-27 include:

• Aeronautics
• Agricultural machinery
• Construction and building
• General engineering
• Textile machinery

Try our dynamic metal selector tool to compare the mechanical and physical properties of different alloys.

Die casting with ZA-27

The high-strength properties of ZA-27, combined with its castability, enable our team of engineers to design for strength while reducing the overall material content compared with alternative materials. We can cast stronger parts with thinner walls using ZA-27. Customers whose parts failed when using A380 switched to ZA-27 and more than doubled their yield strength. Our team of engineers has the experience and expertise to guide you through transitioning your project to ZA-27 or assist you in starting a new project from scratch.